Hydrogen sulfide experimental studies

Extensive research on hydrogen sulfide removal from natural gas was carried out by Tollefson and coworkers [65, 67—72]. The oxidation of hydrogen sulfide was studied in both fluidized and fixed bed reactors at a wide temperature range (398-473 K) and a pressure range between 230-320 kPa with H2S concentration between 0.(K)3 to 6 % and oxygen content from one to four times the stoichiometric ratio with respect to hydrogen sulfide concentration present in the mixture. The typical experimental set up for fixed bed reactor is presented in Fig.25. 

A study by Knights et al. [113] showed the effect of hydrogen sulfide poisoning at various current densities and H2S concentrations over time. They measured the poisoning effect of hydrogen sulfide experimentally and compared it to an empirical relation, which was found by Mohtadi et al. [114], Kim et al. [115], and Amphlett et al. [116] and is given as ... 

Figure 14-12 illustrates the influence of system composition and degree of reaetant eonversion upon the numerical values of for the absorption of CO9 into sodium hydroxide solutions at constant conditions of temperature, pressure, and type of packing. An excellent experimental study of the influence of operating variables upon overall values is that of Field et al. (Pilot-Plant Studie.s of the Hot Carbonate Proce.s.s for Removing Carbon Dioxide and Hydrogen Sulfide, U.S. Bureau of Mines Bulletin 597, 1962). 

Kosmider S, Rogala E, Pacholek A. 1967. Electrocardiographic and histochemical studies of the heart muscle in acute experimental hydrogen sulfide poisoning. Arch Immunol Ther Exp 15 731-740. 

Stewart and Hack (5.) have presented operating characteristics of pressure swing adsorption systems for reducing impurities in a hydrogen stream from 40 vol percent to 1 ppm. Impurities included ammonia, water, methane, carbon monoxide, carbon dioxide, nitrogen, and several hydrocarbons. In this study heatless adsorption is used to separate hydrogen sulfide-hydrogen mixtures and the experimental results are compared with theoretical models. 

Numerous experimental animal studies have examined hydrogen sulfide toxicity. Many of them are summarized below and in Table 7—4. Most animal studies have examined effects at doses well above the proposed SEALs of 10 and 20 ppm. Less information available about the range of lower concentrations that cause eye irritation. The results of the animal studies reviewed are generally consistent with the human data. 

There have been three experimental investigations of the viscosity of liquid hydrogen sulfide. The three studies are summarized in table 2A.1. For the two low-temperature studies, Steele et al. (1906) and Runovskaya et al. (1970), the pressure was probably 1 atm (101.325 kPa), whereas the study of Hennel and Krynicki (1959) was at the vapor pressure of pure H2S. 

The study of Selleck et al. (1952) is considered the benchmark investigation of the system hydrogen sulfide + water. They published tables of smoothed data, which are commonly quoted in the literature. However, these tables are based on relatively few and scattered experimental data points. A discussion of their data was presented in the next appendix. 

They also noted that hydrogen sulfide selectivity over carbon dioxide can be Improved by introducing gas gaps in a multilayer membrane because of the higher reaction rates of hydrogen sulfide. They found that catalysts increased the carbon dioxide hydration rate by a factor of 2 at low carbon dioxide partial pressure, this effect was observed to increase as carbon dioxide partial pressure decreased. Economic studies based on experimental data Indicate that cost savings on the order of 30-50% over conventional acid gas scrubbing were possible with immobilized liquid membranes. 

Aniskin, S.V., Protod yakonov, I.O., and Ionov, V. A., Experimental study of hydrogen sulfide desorption using a monodisperse - droplet generator, Russian J. Appl. Chem., 71, 1158, 1998. 

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